U.S. Pat. No. 3,210,252 discloses oxidation dyeing compositions containing 5-amino-2-methylphenol (1-methyl-2-hydroxy-4-aminobenzene) in combination with p-phenylene-diamine (PPD) or PPD derivatives or p-aminophenol (PAP) or PAP derivatives. In the presence of an oxidizing agent these compositions dye hair brilliant color shades such as gold red, mahogany and Bordeaux. PAP derivatives include compounds such as 3-methyl-4-aminophenol and 2-methyl-4-aminophenol.
U.S. Pat. No. 4,883,656 (the '656 patent) covers compositions for the oxidative dyeing of hair comprising a specific composition of 3-methyl-4-aminophenol, 2-methyl-5-aminophenol and PPD or p-toluenediamine (PTD) or mixtures thereof. Natural red, free of yellow and blue hues, was obtained.
The '656 patent teaches that 3-methyl-4-aminophenol is not good in conventional terms. It is disclosed that "although the developer substance 3-methyl-4-aminophenol is frequently mentioned in publications on hair dyeing, it has achieved very little importance, if any, in practice. Thus, 3-methyl-4-aminophenol with 2-methyl-5-aminophenol as coupler only provides a brick red which is weak in color."
U.S. Pat. No. 4,997,451 ('451 patent) relates to oxidative hair dyeing compositions based on 4-aminophenol derivatives and new 4-aminophenol derivatives.
The '451 patent covers dyeing compositions containing 2-(alkoxymethyl)-4-aminophenol as the developer substance and teaches that "the 4-amino-3-methylphenol, which is a structurally similar compound, results in a considerably reduced color depth than the 4-aminophenol derivatives of the present invention."
U.S. Pat. No. 5,344,463 (the '463 patent) relates to hair dye compositions and methods utilizing 2-substituted-1-naphthol couplers.
The '463 patent deals with dye composition containing 2-substituted-1-naphthol in which the composition imparts a long-lasting red color to hair. The compositions of this patent are taught to be substantially more acid-resistant than dyestuffs prepared through use of the 1-naphthol coupler.
3-Methyl-4-aminophenol is mentioned as one of the primary intermediates in the '463 patent. However, there is no teaching that the combination of 3-methyl-4-aminophenol and 2-methyl-1-naphthol delivers color to hair which is unusually and unexpectedly shampoo- and light-fast.
U.S. Pat. No. 5,500,021 ('021 patent) relates to an oxidation dye composition for keratinous fibers comprising a para-aminophenol, a meta-aminophenol and a meta-phenylenediamine, and dyeing process using such a composition.
The combination of 3-methyl-4-aminophenol, 2-methyl-5-aminophenol and PPD or PTD produces coloration with warm and coppery shades which have good resistance to light, to washing, to bad weather, and to perspiration. The '021 patent teaches that the composition gives resistance to perspiration which is particularly noteworthy and superior to that of the state of the art.
U.S. Pat. No. 5,514,188 discloses oxidation dye compositions for keratinous fibers comprising a 4-aminophenol, 2-methyl-5-aminophenol and p-phenylenediamine and/or a bis(phenylalkylene)diamine.
Combinations of 3-Methyl-4-aminophenol or 2-methyl-4-aminophenol, or 2-hydroxymethyl-4-aminophenol with 2-methyl-5-aminophenol and PPD derivatives produce colorations with red or coppery shades which are resistant to light, to washing, to bad weather, and to perspiration.
U.S. Pat. No. 4,883,656 characterizes 3-methyl-4-aminophenol as achieving very little importance in practice and that compositions containing this intermediate provide a brick red which is weak in color.
U.S. Pat. No. 4,997,451 also teaches that 3-methyl-4-aminophenol produces a considerably reduced color depth than 4-aminophenol.
U.S. Pat. Nos. 4,883,656 and 4,997,451 teach that 3-methyl-4-aminophenol does not produce good color useful enough to use as a hair dye. U.S. Pat. No. 5,500,021 and U.S. Pat. No. 5,514,188 also teach that 3-methyl-4-aminophenol is only useful when it is used in combination with 2-methyl-5-aminophenol and m-diaminobenzene or p-diaminobenzene.